> I do care about the climate, but it's clearly irrational to make sacrifices, when other people are unwilling to do that

We do irrational things daily in order to live harmoniously in groups. Heck, the entire field of behavioural economics was stood on its ear when they figured out that humans don’t behave rationally in all circumstances. Moral choices are individual. I limit my QOL in many “irrational” ways because it helps me live with myself. Is it enough? Of course not. But we are too outnumbered by the greedy and the defeatists.